Novel chitosan-alginate fibres for advanced wound dressings

A range of commercial chitosans were sourced and their molecular size profiles and degrees of acetylation (DA) were determined by HPSEC and H-1-NMR spectroscopy, respectively. Chitosans were subsequently utilised for modification of alginate fibres, and levels of chitosan incorporated into base fibres were estimated by elemental analysis. Elongation (%) and tenacity of resultant chitosan/ alginate fibres were determined in order to assess their potential application in wound dressings. A range of chitosan contents (similar to 0-6 % w/w) resulted from a variety of alginate and chitosan starting materials. Fibres produced from sodium alginate (A1, 6%) using hydrochloric acid (0.2M) at a draw ratio of 1.18, and treated with chitosan (C1, 3.2%) were deemed to have the best properties. In general, use of a water washing stage resulted in the production of better chitosan/alginate fibres. Treatment with chitosans generally resulted in a reduction in tenacity (and a reduction in % elongation if a water washing stage was not used), i.e. no increase in fibre strength was observed, implying that the chitosan is more like a coating rather than penetrating/reinforcing the alginate fibre.